A Flashbots demo

JavaScript

import { ethers } from "ethers";
import {
    FlashbotsBundleProvider,
    FlashbotsBundleResolution,
} from "@flashbots/ethers-provider-bundle";

//const GWEI = 10n ** 9n;
const CHAIN_ID = 1;//11155111; // goerli测试网，如果用主网，chainid 改为 1

// 1. 普通rpc （非flashbots rpc）
const ALCHEMY_GOERLI_URL = 'xxx';
const provider = new ethers.JsonRpcProvider(ALCHEMY_GOERLI_URL);

// 2. flashbots声誉私钥，用于建立“声誉”，详情见: https://docs.flashbots.net/flashbots-auction/searchers/advanced/reputation
// !!!注意: 这个账户，不要储存资金，也不是flashbots主私钥。
const authKey = '0x227dbb8586117d55284e26620bc76534dfbd2394be34cf4a09cb775d593b6f88'
const authSigner = new ethers.Wallet(authKey, provider)

function bigIntReplacer(key, value) {
    if (typeof value === 'bigint') {
        return value.toString();
    } else {
        return value;
    }
}

const main = async () => {

    // 3. flashbots rpc（goerli 测试网），用于发送交易
    const flashbotsProvider = await FlashbotsBundleProvider.create(
        provider,
        authSigner,
        // 使用主网 Flashbots，需要把下面两行删去
        //'https://relay-goerli.flashbots.net/', 
        //'goerli'
        // 'https://relay-sepolia.flashbots.net',
        // 'sepolia'
        'https://relay.flashbots.net',
        'Mainnet'
    );

    const privateKey = '0x3'; // !!! 用于救援的钱包私钥, 主要为了隔离风险.
    const wallet = new ethers.Wallet(privateKey, provider);

    const compromizedPhrase = ''; // !!! 助记词
    const compromizedWallet = ethers.Wallet.fromPhrase(compromizedPhrase, provider);

    console.log(`compromized wallet address: ${compromizedWallet.address}`);

    const saveAddress = '0x'; // !!! 一个安全的地址.

    const contractAddress = '0x'; // !!! 合约地址.

    // Get the base fee for the next block
    const latestBlock = await provider.getBlock('latest');
    // const baseFeePerGas = latestBlock.baseFeePerGas;

    // Set a priority fee ("tip") in GWEI
    const priorityFeePerGas = ethers.parseUnits('10', 'gwei');

    // Calculate the max fee per gas
    const maxFeePerGas = ethers.parseUnits('100', 'gwei');

    const gasLimit = '22000'

    console.log(`gasLimit: ${gasLimit}`)

    const nonce0 = await wallet.getNonce()
    console.log(`nonce0: ${nonce0}`);

    console.log(`wallet balance: ${ethers.formatEther(await provider.getBalance(wallet))} ETH`);

    // process.exit();

    // 4. 创建一笔交易
    // EIP 1559 transaction
    const transaction0 = {
        chainId: CHAIN_ID,
        type: 2,
        nonce: nonce0,
        to: compromizedWallet.address,
        value: ethers.parseEther("0.007"), // 0.01
        gasLimit: gasLimit, // Set the minimum gas limit for a simple transfer
        maxPriorityFeePerGas: priorityFeePerGas, // The priority fee
        maxFeePerGas: maxFeePerGas, // The maximum fee per gas you are willing to pay
    }
    const signedTx0 = await wallet.signTransaction(transaction0);

    const abi = '';// !!! 合约abi
    const contract = new ethers.Contract(contractAddress, abi, compromizedWallet)
    const data = contract.interface.encodeFunctionData("streamWithdraw", [ethers.parseEther('0.5'), "yo~"])
    const nonce1 = await compromizedWallet.getNonce();
    console.log(`nonce1: ${nonce1}`);
    const transaction1 = {
        chainId: CHAIN_ID,
        type: 2,
        nonce: nonce1,
        to: contractAddress,
        data: data,
        gasLimit: "50000", // Set the minimum gas limit for a simple transfer
        maxPriorityFeePerGas: priorityFeePerGas, // The priority fee
        maxFeePerGas: maxFeePerGas, // The maximum fee per gas you are willing to pay
    }
    const signedTx1 = await compromizedWallet.signTransaction(transaction1)

    const nonce2 = nonce1 + 1
    console.log(`nonce2: ${nonce2}`);
    const transaction2 = {
        chainId: CHAIN_ID,
        type: 2,
        nonce: nonce2,
        to: saveAddress,
        value: ethers.parseEther("0.5"),
        gasLimit: gasLimit, // Set the minimum gas limit for a simple transfer
        maxPriorityFeePerGas: priorityFeePerGas, // The priority fee
        maxFeePerGas: maxFeePerGas, // The maximum fee per gas you are willing to pay
    }
    const signedTx2 = await compromizedWallet.signTransaction(transaction2)

    // 5. 创建交易 Bundle
    const transactionBundle = [
        {
            signedTransaction: signedTx0
        },
        {
            signedTransaction: signedTx1
        },
        {
            signedTransaction: signedTx2
        }
    ]

    console.log("start!!!");

    console.log(`wallet balance: ${ethers.formatEther(await provider.getBalance(wallet))} ETH`);

    // 6. 模拟交易，交易模拟成功后才能执行
    // 签名交易
    const signedTransactions = await flashbotsProvider.signBundle(transactionBundle)

    console.log("---1---");

    // 设置交易的目标执行区块（在哪个区块执行）
    const targetBlockNumber = (await provider.getBlockNumber()) + 1

    console.log(`target block number: ${targetBlockNumber}`)

    // 模拟
    const simulation = await flashbotsProvider.simulate(signedTransactions, targetBlockNumber)
    // 检查模拟是否成功
    if ("error" in simulation) {
        console.log(`模拟交易出错: ${simulation.error.message}`);
        process.exit(1);
    } else {
        console.log(`模拟交易成功`);
        console.log(JSON.stringify(simulation, bigIntReplacer, 2))
    }

    // 7. 发送交易上链
    // 因为测试网Flashbots的节点很少，需要尝试很多次才能成功上链，这里我们循环发送 100 个区块。
    for (let i = 1; i <= 100; i++) {
        let targetBlockNumberNew = targetBlockNumber + i - 1;
        // 发送交易
        const res = await flashbotsProvider.sendRawBundle(signedTransactions, targetBlockNumberNew);
        if ("error" in res) {
            throw new Error(res.error.message);
        }
        // 检查交易是否上链
        const bundleResolution = await res.wait();
        // 交易有三个状态: 成功上链/没有上链/Nonce过高。
        if (bundleResolution === FlashbotsBundleResolution.BundleIncluded) {
            console.log(`恭喜, 交易成功上链，区块: ${targetBlockNumberNew}`);
            console.log(JSON.stringify(res, null, 2));
            process.exit(0);
        } else if (
            bundleResolution === FlashbotsBundleResolution.BlockPassedWithoutInclusion
        ) {
            console.log(`请重试, 交易没有被纳入区块: ${targetBlockNumberNew}`);
        } else if (
            bundleResolution === FlashbotsBundleResolution.AccountNonceTooHigh
        ) {
            console.log("Nonce 太高，请重新设置");
            process.exit(1);
        }
    }
}

main()